(after stating the facts as above). Without considering the question of infringement or the, defense of aggregation, we are satisfied that the claim sued upon is invalid for lack of invention. The structure recited in .the claim is merely'the application to a holding card and bill hook of the common mechanical expedient by which a slidable and rotatable shaft may at one end of its sliding movement be locked in any desired position of rotation by engagement between a projection carried by the shaft and independently-carried means for engaging the shaft projection. Whether we should take judicial notice that this mechanical idea is in common use, or whether there might be invention in first applying the idea to the card and bill hook combination, we need not consider, because the record shows earlier applications of the same idea to the same combination.
The patent to Studabaker, No. 615,921, of December ‘ 13, 1898, shows, except' in the particulars to be stated, the same combination, to be used in the same way, to accomplish the same results. See discussion. of the Studabaker patent, and of the prior art, by Judge Hazel in Whitehead v. Bastian (C. C.) 167 Fed. 565. Studabaker shows several'forms; between one of them, his Figure 3, and Hornich, as illustrated by his Figure 5, the differences are two: The-top of the shaft, instead of being bent to form a hook, is bent to. form an eye;' and in*738stead of the hook dropping into a socket in the plate, the eye is held by the plate itself against rotation. The differences are made clear by these drawings:
This being the field into which Hornich came, we cannot think that it involved invention to change the Studabaker eye into a hook and to provide a receiving socket for the hook. The hook and the eye are alike mere offsets from the shaft; the contact between the eye and plate, and between hook and socket, alike form engaging means to resist rotation. Hornich’s locking effect is very likely more perfect;. but it is at best only a slight improvement, and by simple and obvious means. Galvin v. Grand Rapids (C. C. A. 6) 115 Fed. 511, 517, 53 C. C. A. 165; American Carriage Co. v. Wyeth (C. C. A. 6) 139 Fed. 389, 391, 71 C. C. A. 485; Macomber, § 654.
The decree of the District Court is affirmed, with costs.